The exotic may seem underwhelming at first look because of the Arc barrel explosion in the trailer compared to what it really does. However, it does rip through enemies fairly quickly whether they are Taken or not. Not to mention if you're running in a fireteam the slugs stack with your teammates. If you hit 3 and they hit 2 it still triggers the explosion. Works the same in Crucible. Can't tell you how many times my buddy has hit a dude 2 or 3 times and almost died so he backed up and I'd hit enough to trigger the explosion and watch them die from it. Yes it's underwhelming compared to the trailer but it's still a monster in it's own right.